Manufacture of diaminodiarylketones and product thereof



Patented Feb. 20, 1940;

* UNITED STATES FPATENT 3 o-F FIC MANUFACTURE OF DIADIINODIARYLKE- TONESAND PRODUCT THEREOF Gustav Reddelien, Leipzig, and Georg Matthaeus,Wolfen, Kreis Bitterfeld, Germany, assignors'to General Aniline & FilmCorporation, a. corporation of Delaware No Drawing. Application July 28,1937, Serial No. 156,143.. In Germany August 26, 1936 4 Claims.

The process which produces Michlers ketone,

namely the reaction of substituted aromatic amines with phosgene is notapplicable as a general method. 5 This invention relates to themanufacture of Michlers ketone and other similar ketones which areaccessible only with difficulty, by causing the corresponding hydrols toreact with hydrazines of the aromatic series in the presence of a smallproportion of acid, then oxidizing the condensation products thusobtained and converting them into ketones by acid scission. The courseof the reaction may be supposed to be as follows:

Mono:

mont N( a)2 In these formulae Ar is an aromatic radicle, preferablyphenyl.

Such ketones are not obtainable by direct oxidation of hydrols. However,the new process 40 produces a good yield by oxidation of thephenylhydrazones of the ketone which by acid scission pass into theketone.

The following example illustrates the invention, the parts being byweight: 45 27 parts of tetramethyldiaminobenzhydrol are dissolved in 100parts of alcohol and the solution is mixed with 10.82 parts ofphenylhydrazme. To this mixture is added 0.3 to 0.5 part of2-N-hydrochloric acid. The condensation product soon.

50. separates in the form of crystals, which are filtered after havingstood for some hours, washed and dried. The yield of the pure substance,which melts at 119 C., amounts to 82 per cent.

18 parts of the anilidoleucauramine are oxi- 55 dized in 200 parts ofacetone and 10 parts of water with the calculated proportion ofpotassium permanganate. The manganese oxides produced are separated andextracted with benzene. The filtrates are distilled in steam. When theresidue in the retort hascooled, it is boiled with dilute hydrochloricacid] From the cooled solution a precipitate is produced by addition ofdilute caustic soda solution; this is phenylhydrazone of the Michlersketone of melting point 130 to 140. C.; by scission with acidthephenylhydrazone yields the Michlers ketone of melting point 172 C. in ayield of 75 per cent. In a corresponding manner there may be obtained,for example, other paratetraalkyldiaminobenzophenones which may containnuclear substituents such as alkyl, halogen,

alkoxy and so on. Thus, tetrabutyldiaminobenzophenone is obtainable witha yield of 50 per; I

contain hydroxyalkyl groups in amino groups and symmetricaldihyroxyethyldibutyldiaminobenzophenone maybe obtained with a yield of60 wherein a: and y are members of the group consisting of alkyl andhydroxyalkyl with phenylhydrazine in an alcoholic solution in thepresence of a catalytic amount of an acid, oxidizing the condensationproduct thus obtained and subjecting it to acid scission.

2. The process which comprises reacting tetracent. Furthermore, thetertiary diamines may i methyldiaminobenzhydrol with phenylhydrazine analcoholic solution in the presence of a cataof a catalytic amoun t of anacid, oxidizing the condensation product thus obtained and subjecting itto acid scission.

4. Dihydroxyethyldi butyldiaminobenzophenone.

GUSTAV REDDELIEN. GEORG MATTHAEUS.

